U.S. patent number 5,027,499 [Application Number 07/341,641] was granted by the patent office on 1991-07-02 for method for fabricating a channel device and tube connection.
This patent grant is currently assigned to Otto Sensors Corporation. Invention is credited to Otto J. Prohaska.
United States Patent |
5,027,499 |
Prohaska |
July 2, 1991 |
Method for fabricating a channel device and tube connection
Abstract
The invention is concerned with a method for manufacturing a
channel device, especially for recordings of thermal conductivity,
viscosity, density, dielectric constants, refractive indices, etc.
of materials such as fluids and gases (called samples), where the
material under investigation is guided through a measuring channel
with at least one sensor and at least one inlet and one outlet
orifice for the sample. The invention also concerns the fabrication
procedure of the channel device, especially the recording unit for
determining the thermal conductivit, viscosity, density, dielectric
constant, etc. of samples where the material under investigation is
passed through or brought into a measuring channel which is
equipped with sensors and actuators.
Inventors: |
Prohaska; Otto J. (Cleveland
Heights, OH) |
Assignee: |
Otto Sensors Corporation
(Cleveland, OH)
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Family
ID: |
3552234 |
Appl.
No.: |
07/341,641 |
Filed: |
April 21, 1989 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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936887 |
Dec 2, 1986 |
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Foreign Application Priority Data
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Dec 9, 1985 [AT] |
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A3562/85 |
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Current U.S.
Class: |
29/595; 216/99;
29/424 |
Current CPC
Class: |
G01N
27/221 (20130101); G01N 25/18 (20130101); G01N
21/17 (20130101); G01N 11/02 (20130101); G01N
30/6095 (20130101); G01N 21/41 (20130101); G01N
30/6052 (20130101); Y10T 29/49812 (20150115); G01N
2201/0622 (20130101); Y10T 29/49007 (20150115); G01N
21/85 (20130101) |
Current International
Class: |
G01N
21/17 (20060101); G01N 27/22 (20060101); G01N
11/00 (20060101); G01N 11/02 (20060101); G01N
25/18 (20060101); G01N 21/85 (20060101); G01N
21/41 (20060101); G01N 30/00 (20060101); G01N
30/60 (20060101); G01R 003/00 () |
Field of
Search: |
;29/593,423,424,852,853,846,595 ;156/644,656,659.1,661.1,901,902
;204/406,411,424,425 ;427/96,97,264,265
;73/864.83,864.84,866,863.84 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Eley; Timothy V.
Assistant Examiner: Vo; Peter Dungba
Attorney, Agent or Firm: Calfee, Halter & Griswold
Parent Case Text
This is a divisional of co-pending application Ser. No. 06/936,887
filed on Dec. 2, 1986. Now abandoned.
Claims
I claim:
1. A method for manufacturing a device for measuring at least one
characteristic of a fluid by passing such fluid through a measuring
channel of appropriate dimensions for measuring such
characteristic; said method comprising the steps of:
providing a support member having an inlet orifice and an outlet
orifice;
depositing a channel-forming dissolvable material on the support
member in a path which spans between the inlet and outlet
orifices;
controlling the shape of the path of dissolvable material to obtain
a measuring channel having appropriate dimensions for measuring
said one characteristic of the fluid;
forming a wall by depositing a wall-forming material onto the
support member and onto and around the path of passage-forming
dissolvable material by a process selected from a group consisting
of evaporation, spin on, drop on, sputtering, and reactive
deposition, whereby a wall is formed which substantially covers the
path of channel-forming dissolvable material and which covers at
least parts of the support member;
dissolving and removing the path of channel-forming dissolvable
material through at least one of said orifices by introducing a
solvent which dissolves the path of dissolvable material but which
does not interact with the support member and the wall, whereby a
measuring channel of appropriate dimensions is formed which spans
between the inlet orifice and the outlet orifice, whereby inner
surfaces of the support member and the wall define the measuring
channel and whereby the support member and wall form a housing
surrounding the measuring channel; and
providing at least one sensor for measuring at least one
characteristic of such fluid as it passes through the measuring
channel by attaching and arranging the sensor in a sensing position
relative to the housing by a process which is a member of a group
consisting of evaporation, spin on, drop on, sputtering, reactive
deposition, chemical vapor deposition, plasma enhanced chemical
vapor deposition, and ion implantation whereby the housing and
sensor form a sensor-housing unit.
2. The method as set forth in claim 1 wherein the step of forming
the wall includes depositing on the dissolvable material a material
selected from a group consisting of synthetic resin, glass, ceramic
Si.sub.3 N.sub.4, SiO.sub.2, SiO, and combinations thereof.
3. The method as set forth in claim 1 further comprising the step
of depositing a cover layer on top of at least a portion of said
sensor-housing unit.
4. The method as set forth in claim 1 further comprising the step
of etching the inner surfaces of the support surface and the wall
which define the measuring channel.
5. The method as set forth in claim 1 further comprising the step
of passivating the inner surfaces of the support surface and the
wall defining the measuring channel.
6. The method as set forth in claim 1 wherein said step of
providing a support member includes providing a substrate having
two openings, one opening forming the inlet orifice and the other
opening forming the outlet orifice.
7. The method as set forth in claim wherein said step of providing
a support member includes the steps of:
providing a substrate:
attaching a first tube to the substrate to form the inlet orifice;
and
attaching a second tube to the substrate to form the outlet
orifice.
8. The method as set forth in claim 1 wherein said step of
dissolving and removing includes the step of removing said
dissolvable material through at least one of said orifices.
9. The method as set forth in claim 1 wherein said step of
providing a support surface includes the steps of:
providing a substrate;
attaching a plurality of tubes to the substrate to form a plurality
of inlet orifices; and
attaching a plurality of tubes to the substrate to form a plurality
of outlet orifices.
10. The method as set forth in claim 1 wherein said step of
providing a support member comprises the steps of providing a
substrate; and attaching at least one tube to the substrate to form
at least one of said orifices, and wherein the step of forming the
wall includes the step of depositing the channel-forming
dissolvable material on at least a portion of the tube.
11. The method as set forth in claim 10 wherein the step of
attaching at least one tube to the substrate includes the step of
attaching a tube having a nozzle-like opening.
12. The method as set orth in claim 10 further comprising the step
of forming an indentation in the substrate for receiving the one
tube.
13. A method of manufacturing a device for measuring at least one
characteristic of a fluid by passing such fluid through a measuring
channel of appropriate dimensions for measuring such
characteristic, said method comprising the steps of:
providing a substrate;
attaching at least one tube to the substrate to form a first
orifice;
providing the substrate with a second orifice;
depositing a channel-forming dissolvable material on the substrate
in a path which is of a shape corresponding to such appropriate
dimensions of such measuring channel of the measuring device and
which spans between the first and second orifices;
depositing a wall-forming material onto the path of the
passage-forming dissolvable material and onto a portion of the tube
by a process selected from a group consisting of evaporation, spin
on, drop on, sputtering, reactive deposition, whereby a wall is
formed which substantially covers the path of channel-forming
dissolvable material and which covers a portion of the tube;
dissolving and removing the channel-forming dissolvable material
through at least one of the orifices by introducing a solvent which
is capable of dissolving the dissolvable material but which does
not interact with the substrate and the wall whereby the measuring
channel of appropriate dimensions is formed which spans between the
first and second orifices, and whereby the substrate, the tube and
the wall form a housing surrounding the measuring channel;
providing at least one sensor for measuring such one characteristic
of such fluid as it passes through the measuring channel by
attaching and arranging the sensor in a sensing position relative
to the housing by a process selected from a group consisting of
evaporation, spin on, drop on, sputtering, reactive deposition,
chemical vapor deposition, plasma enhanced chemical vapor
deposition, and ion implantation.
14. The method as set forth in claim 13 wherein said step of
dissolving and removing includes the step of removing said
dissolvable material through at least one of said orifices.
15. A method for manufacturing a device for measuring at least one
characteristic of a fluid, said device having a wall defining a
measuring channel of a certain shape, an inlet orifice and an
outlet orifice for conducting fluid into and out of the measuring
channel, and at least one sensor for measuring at least one
characteristic so the fluid which flows through the measuring
channel, said method comprising the steps of:
providing a support member having an inlet orifice and an outlet
orifice;
depositing a channel-forming dissolvable material on the support
member in a path which spans between the inlet and outlet orifices
and having a shape corresponding to the shape of the measuring
channel of the measuring device;
controlling the shape of the path of dissolvable material to obtain
a measuring channel having appropriate dimensions for measuring
said one characteristic of the fluid;
forming a wall by depositing a wall-forming material onto the
support member and onto and around the path of passage-forming
dissolvable material by a process selected from a group consisting
of evaporation, spin on, drop on, sputtering, and reactive
deposition, whereby a wall is formed which substantially covers the
path of channel-forming dissolvable material and which covers at
least parts of the support member;
wherein this step of forming the wall includes depositing on the
first body of dissolvable material the second body of material
selected from a group consisting of synthetic resin, glass, ceramic
Si.sub.3 N.sub.4, SiO.sub.2, SiO, and combinations thereof;
dissolving and removing the path of channel-forming dissolvable
material through at least one of said orifices by introducing a
solvent which dissolves the path of dissolvable material but which
does not interact with the support member and the wall, whereby a
measuring channel of appropriate dimensions is formed which spans
between the inlet orifice and the outlet orifice, whereby inner
surfaces of the support member and the wall define the measuring
channel and whereby the wall and the support member form a housing
surrounding the measuring channel; and
arranging and attaching at least one sensor in a sensing position
relative to the housing by a process which is a member of group
consisting of evaporation, spin on, drop on, sputtering, reactive
deposition, chemical vapor deposition, plasma enhanced chemical
vapor deposition, and ion implantation whereby the housing and
sensor together form a sensor-housing unit; and
depositing a cover layer on top of at least a portion of said
sensor-housing unit.
Description
BACKGROUND OF THE INVENTION
The invention is concerned with a channel device, especially for
recordings of thermal conductivity, viscosity, density, dielectric
constants, refractive indices, etc. of materials such as fluids and
gases (called samples), where the material under investigation is
guided through a measuring channel with at least one sensor and at
least one inlet and one outlet orifice for the sample. The
invention also concerns the fabrication procedure of the channel
device, especially the recording unit for determining the thermal
conductivity, viscosity, density, dielectric constant, etc. of
samples where the material under investigation is passed through or
brought into a measuring channel which is equipped with sensors and
actuators.
The aim of the invention is to create a measuring arrangement
capable of on-line recordings which is extremely sensative even for
a very small sample volume and can be miniaturized for mass
production, using photolithographic, thin-film and solid-state
techniques. The invention is characterized by a channel, formed by
a substrate (or carrier) and a layer, forming a wall, which is
arranged a certain distance from the substrate. The layer is
deposited by evaporation, spin-on, sputter, drop-on, reactive
deposition, CVD, PECVD, etc., techniques and consists ie. of
synthetic material, glass, ceramic, Si3N4, SiO2, SiO, combinations
of these materials, etc. The invention is also characterized by the
fact that the sensors and actuators are formed by layers on and/or
in the substrate and /or in the wall forming layer, ie. by
evaporation, spin-on, sputter, drop-on, reactive deposition, CVD
(chemical vapor deposition), PECVD (plasma enhanced chemical vapor
deposition), etc. techniques.
The process invention is characterized as follows: a dissolvable
substance is deposited on the substrate, forming the inside of the
channel, consisting of ie. photoresist, synthetic material etc. The
dissolvable substance is covered afterwards by the wall forming
layer, which also covers at least parts of the substrate where the
substrate is free of dissolvable substance. The layer adheres well
on the substrate and forms, together with the substrate, the
measuring channel. The dissolvable substance can be dissolved and
removed through the inlet and outlet orifices using solvents and
solutions which are not dissolving or attacking the wall forming
layer or the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1a, 1b and 1c depict a cross-sectional view of the channel
device of the present invention; FIGS. 2 and 2b depict a
cross-sectional view of a channel device for measuring viscosity
and dielectric constants;
FIG. 2a is a graph depicting the slope of capacitance change and
velocity of a sample in the calculation of viscosity;
FIG. 3 is a schematic of a device consisting of a transmitter and
receiver for measuring sample density;
FIG. 3a is a cross-secional view showing the location of the
transmitter and receiver relative to the substrate;
FIG. 4 is a view showing the connection of tubes to the substrate
and channel layer by an adhesive layer;
FIG. 5 is a cross-sectional view showing inlet and outlet tube
positions relative to the sensor positions;
FIG. 6 is a side view depicting the indentation of the tubes in the
substrate;
FIG. 7 schematically depicts the connection of the tube to the
substrate via an adhesive layer; and
FIGS. 8 and 9 are top views of a multiple tube/multiple channel
device. Preferred or advantageous arrangements of the invention, as
well as the detailed procedures, are to be found in the sub-claims,
the descriptions and the schematic drawings.
DETAILED DESCRIPTION
Furthermore, it is the aim of the invention to establish
connections to thin tubes in order to conduct fluids or gases in or
out of the miniaturized measuring arrangements such as described,
ie., in this invention. The invented tube connection is
characterized by the fact that onto at least one tube, which can be
connected to the substrate (ie. glued on), at least one layer is
deposited ie. by evaporation, drop-on procedure, sputtering,
spin-on, reactive deposition, CVD, PECVD. etc., in such a way that
the endings of the tubes are kept open and the layer is tightly
connected with the tube and the substrate and establishes and
defines a free space together with the substrate in such a way that
this free space becomes a continuation of the inside of the
tube.
The fabrication procedure for such a connection is characterized,
according to the invention, in that a dissolvable substance, ie.
photoresist, synthetic resin, etc., is deposited onto a substrate
as well as into a tube which can be mounted (ie. glued) onto the
substrate in such a way that this dissolvable substance forms a
continuation of the tube. A layer is then deposited onto the
dissolvable substance so that it covers this substance as well as
at least a part of the tube and at least a part of the substrate
and forms a tight and sealing connection with the tube as well as
with the substrate. The deposition of the layer may be performed by
evaporation, drop-on, sputtering, spin-on reactive deposition, CVD,
PECVD, etc. The dissolvable substance can be dissolved and removed
through the open end(s) of the tube and/or through the open end of
the continuation which was formed by the dissolvable substance,
using a solvent or procedure which will not affect the substrate or
the layer or the tube.
Preferred designs of the tube connections and procedures for the
fabrication of these connections can be found in the subclaims, the
description and the drawings.
The evaluation and analysis of the measurements if performed by
electronic devices which are connected to sensors and actuators
which are arranged in and/or on the layer and/or in and/or on the
substrate. The temperature raise of the heating layers, the
creation of surface accoustic waves and all other actuations which
are necessary for proper recordings, can be generated by
appropriate electronic devices.
It is easy to see that recording arrangements, which are differing
from the ones described above, and can be produced, using the
invented fabrication techniques, ie. miniaturized chromatographs,
pH-meters, pressure sensors, etc.
The selection of the dissolvable substances and their solvents can,
to a large extent, be left to specialists. The schematic drawings
will explain the invention: FIG. 1 shows a channel device which is
especially designed for recording thermal conductivity and
viscosity of a fluid or a gas. A layer(2) is deposited on a
substrate(1) in such a way that a measuring channel is formed which
has at least one inlet orifice(4) and one outlet orifice(5). The
layer(2) is deposited onto the substrate(1) in such a way that a
dissolvable substance is first deposited which has the shape of the
measuring channel(3) on top of which the layer(2) is deposited,
covering the dissolvable substance and at least parts of the
substrate(1), so called boundary parts(2'), on which the layer(2)
adheres tightly. Then, the dissolvable substance will be dissolved
through the inlet and/or outlet orifices(4,5). Thus, the measuring
channel(3) is formed by the substrate(1) and the layer(2).
Actuators and/or sensors can be arranged on and/or in the
substrate(1) and/or on and/or in the layer(2) in order to equip the
measuring channel(3) with the desirable recording, sensing, and/or
actuating units. The various sensor and/or acutator layers on
and/or in the substrate(1) as well cover layers(8) on the
substrate(1) are to be deposited before the deposition of the
dissolvable substance. It is, however, possible to subsequently
passivate the inside of the measuring channel(3) by inserting cover
layers(8'') (FIG. 1c) or to increase the measuring channel(3) by
etching or to modify the characteristics of the actuators and/or
sensors by appropriate surface treatments. Heating layers (6,6')
are shown as an example in FIG. 1 in an indentation in the
substrate(1) and on the layer(2), which can be formed by
evaporation, implantation, doping, etc. The electrical connections
to these actuators are not shown. Temperature sensors (7,7') are
arrranged in the substrate(1) and on the layer (2). The temperature
sensors(7,7') can consist of semiconductor layers, doped layers,
metal layers, etc. FIG. 1c shows the layers 6' and 7' as being
contained in layer(2); they can also be covered by a cover
layer(8''). That is possible in particular if the layer(2) or the
substrate(1) consists of silicon which can be formed into a sensor
or actuator by doping or reactive deposition. in this case the
layer(2) or the substrate(1) is part and/or basis for the sensor of
acuator units.
The layers (6 and 7) can be, as shown in FIG 1, deposited in
indentations in the substrate(1) or on the substrate(1) (FIG. 1a).
The layers (6 and 7) can also be covered by a cover layer(8) in
order to prevent modifications of the layers (6 and 7). Another
layer (9) can be put on top of layer (2) and the layers (6' and 7')
which can also be thicker to mechanically stabilize the channel
device.
The deposition of the layers (2,8,9,8' etc) can be performed by
drop on, or spread on, sputtering, evaporation, spin on, etc
procedures. The thickness of the layer(2) is advantageously between
1 um and 50 um, the height of the measuring channel(3) up to 50 um,
the width of the measuring channel(3) can be between 1 um and 500
um and the length might be up to several 10 mm. These values can be
changed, however, depending on the various applications. In most
cases it might be advantageous to have the height of measuring
channel(3) much smaller than the width in order to provide an
optimum contact between the sample and the sensors and actuators.
The thickness of the sensor and actuator layers is usually in the
range of 0.2 um and 40 um.
The viscosity measurement (FIG. 1b) is performed by applying a heat
pulse through the heating layer (6,6') onto the sample gas or
liquid, which flows through the measuring channel, and measuring
the resulting temperature change of the sample with the temperature
sensors 7 and/or 7'. The time between the heat pulse application
and the temperature change, measured with the sensors 7 or 7'
determines the velocity of the sample in the solution which, in
turn, is inverse proportion to the viscosity. The pressure
difference between the inlet(4) and outlet(5) of the measuring
channel(3) has to be known or controlled and can be measured with
pressure sensors(7''). Pressure sensors can be avoided in case of
using a reference measuring channel(3) and the same pressure
difference in both channels. Thermal conductivity can be measured
by applying a certain amount of heat with a certain amplitude
course and detecting the occurance of the temperature maximums, the
amplitude course and the decrease of the maximum at the temperature
sensors (7) (FIG. 1c).
All the explanations for FIG. 1 are in principle valid also for the
following figures and the described characteristics can be combined
with the following ones:
FIG. 2 shows a channel device for recording viscosity and/or
dielectric constants. This channel device is in principle designed
similar to the one described in FIG. 1: conducting layers(10,10')
are deposited on the substrate(1) and the layer(2), forming a
capacitor. As soon as the sample moves into and through the
measuring channel(3), which was previously filled with air or was
evacuated, the capacitance of the layers(10,10') will be changed,
as shown in FIG. 2a. The slope of the capacitance change is
proportional to the velocity of the sample in the measuring
channel(3) and permits the calculation of the viscosity.
It is advantageous, and increases the accuracy of the device, if
the height of the measuring channel(3) has the same value as the
thickness of the cover layer(8') in FIG. 2.
The dielectric constant can be determined from the capacitance of
the device as soon as the measuring channel(3) is completely filled
with the sample.
FIG. 2b shows a possible design of the channel device where the
substrate(1) consists of a basic material (ie. silicon or p-doped
Si) (1') topped by an n-doped layer(1''), forming a barrier layer.
Viscosity and dielectric constant measurements can be performed as
described above.
Density measurements of the sample can be performed by the device
shown in FIG. 3 and FIG. 3a. Transmitter(11) and receiver
layers(12) are arranged on indentations or on the surface of a
piezoelectric substrate. The transmitter layers(11) are connected
to high frequency generators(13), supplying 20 to 50kHz in the low
voltage range and generating surface accoustic waves in the
substrate(1). The resonance signal, detected by the receiver
layer(12), can be changed or damped in dependance of the density of
the sample in the measuring channel(3).
FIG. 4 shows two tubes(17) connected to the substrate(1), ie. by an
adhesive layer(15). The two tubes(17) are connected to a layer(2)
which forms a channel(18) with the substrate(1), adhering tightly
to the tubes(17) and the substrate(1) as well. The transition
between the layer(2) and the tubes(17), kinks, exposed bends, etc.
can be strengthened mechanically by supporting layers(16)
consisting of the same material or a material different from that
of layer(2). The fabrication of such a connection is performed by
depositing a dissolvable substance onto the ends of the tubes(17)
and onto the substrate(1) with the desired shape of the
channel(18). The shape of the dissolvable substance can be
obtained, for instance, by photolithographic processes. The
layer(2) will be deposited onto the dissolvable substances in such
a way that the layer(2) forms a tight connection with the tubes(17)
and the substrate(1). The dissolvable substance will be dissolved
through the tubes (17). This technique allows the design of
connections between and to tubes of various, especially very small,
dimensions.
FIG. 5 shows a design, appropriate to forming inlet and outlet
orifices(4,5) of measuring channels(3). The tubes(17) replace the
orifices(4,5) in the substrate(1). The design of the measuring
arrangement with sensors and actuators can be as described in FIGS.
1 to 3. The layers(2) can be covered by a protective layer(16')
which can be deposited in the same way as layer(2) consisting of
the same, or a different material (ie. glue), as layer(2). The
endings of the tubes(17) can be tilted.
FIG. 6 shows that the tubes (17), especially their endings, can be
covered by the layer(2) and thereby tightly connected to the
substrate(1). The layer(16) can be of additional support and
increase the adhesion of the tubes(17) to the substrate(1). FIG. 6
also shows the tubes(17) can be placed in indentations(19) in the
substrate(1). The cross section of the tubes(17) can be of any
shape, ie. round, rectangular, etc. The same techinques which
permit the production of tube connections also permit the
fabrication of special tube continuations (FIG. 7): a tube(17)
which can be connected by an adhesive layer to a substrate(1) will
be covered at its one ending by a dissolvable substance which also
covers the substrate(1), being especially shaped at this part, ie.
like a nozzle. The layer(2) will be deposited onto at least part of
the tube(17), at least parts of the dissolvable substance and at
least parts of the substrate(1). The dissolvable substance will be
dissolved, leaving a nozzle-like continuation of the tube(17),
formed by the layers(2) and the substrate(1), and which can be used
ie. for injection of substances into the body tissue, etc. A
similar nozzle-like extension of the tube(17) is also shown in FIG.
4, created by the layer(2'), which can be mechanically protected
and /or strengthened by an additional layer(16).
FIG. 8 shows several tubes(17) which are not necessarily arranged
in parallel, and which are connected by a channel(3) which is
formed by the layer(2) and the substrate(1). The endings of the
tubes(17) on the lefthand side of FIG. 8 are combined by the
measuring channel(3) of decreasing cross sections. The measuring
channel(3) finally splits up into several channels which can have
different cross sections, each of which can be connected to a
tube(17). The described invention allows the fabrication of almost
any kind of bifurcation, cross section and channel shape in order
to establish connections of, and among, numerous tubes creating the
possibility of forming valve-like control elements, flow
regulators, etc.
It is also possible to etch the measuring channel (3) as shown in
FIG. 8 into the substrate (1) in order to achieve a smooth
transition between the tubes (17) and the measuring channel (3).
Preferable diameters of the tubes (17) for the described
fabrication procedures are in the range between 5 um and 500 um. It
is also possible to connect two tubes (17) with each other which
are placed next to each other or located in such a way that their
ends are almost touching each other.
The invented channel devices and the tube connections can be used
for investigations of body and tissue liquids, for delivery of
substances to various ie. nerves, organs, etc. and for industrial
applications, ie. ink jet recorders, fuel injection systems, or
other devices where pipe systems, consisting of fine tubes, have to
be connected to each other or external, macroscopic, supply
systems. A big advantage of the invention is also that the
described channel devices yield precise results also in case of
extremely small sample volumes, representing unique measuring units
regarding response time, accuracy, resolution and
reproductibility.
The materials forming the layer (2) or (16) can consist of organic
substances, such as synthetic resin, polymers, epoxy resin, ect. or
any other organic substances such as Si3N4, SiO2, SiO, SiC, ect. or
substances with similar mechanical and or electrical qualities.
The connections to the sensors and actuators can be established by
thin film interconnect paths, deposited in similar ways as
described above.
It is, of course, possible that one measuring channel (3) contains
several sensors and/or actuators and combinations thereof which can
be arranged on and/or in the substrate (1) and/or on and/or in the
layer (2).
Light sources and light detectors can be used for refraction index
measurements: light can be, for instance, transferred through a
light permeable layer (2) and light detectors will measure
reflected and or transmitted light intensities which can be used,
for instance, in order to calculate the refraction index of the
sample. The light can also be transmitted through the tubes (17) or
the tubes (17) can be replaced by optical fibers.
All these values, of course, can be used in order to determine and
analyze the composition of the sample.
FIG. 9 shows a device for flow regulations; the flow of a sample,
ie. from tube (17') to tube (17") in the channel, formed by layer
(2), can be changed or totally directed into the tube (17"").
Miniaturized valve and flow control units can be fabricated.
FIG. 3a shows, in dashed lines, the connections of the substrate
(1) to a supporting substrate (1'") which ie. could be an IC
socket, consisting of a gold plated surface, which can be, in a
well known way, sealed to a Si substrate (1). Tubes can be soldered
to the substrate (1'") forming inlet (4') and outlet (5') orifices
for the measuring channel (3). the sensors can be connected via
wires (21) through ceramic feed throughs (20).
A temperature sensor (22) and a heating layer (23) is shown in FIG.
2ballowing evaporation heat measurements. For that reason, a
channel is filled with the sample, the temperature of which will be
measured. The evaporating sample attracts evaporation heat from the
environment, which can be measured by the sensor (22). The
temperature slope is shown in FIG. 2a by the dashed line. The
evaporation heat can be calculated from the time course of the
temperature between To (temperature in the beginning of the
measurement, where the measuring channel is filled with the sample)
and T1 (end temperature, where the measuring channel is empty).
Capacitance measurements can be performed at the same time,
determining the amount of the substance in the channel, ect.
It is obvious that sensors and actuators, as shown in FIG. 2, can
be arranged next and/or above each other.
BRIEF SUMMARY OF THE INVENTION
The invention discloses the construction of a channel device for
the recording of thermal conductivity, viscoisty, density,
dielectric constant, ect. of liquids and/or gases (sample), where
the sample is directed through a measuring channel, with at least
one inlet and one outlet orifice, containing at least one sensor
unit and is characterized in that a measuring channel is
established by the substrate and a layer, forming a wall, which is
arranged in a certain, predetermined distance and fabricated ie. by
evaporation, spin on, sputtering, drop on, ect. procedures, where
the layers can consist of synthetic resin, glass, ceramic, ect. and
in that measuring units are deposited in layers in and/or on the
substrate and/or in and/or on the wall forming layer.
The invention also discloses the fabrication procedure for the
channel device, characterized in that a dissolvable substance (ie.
photoresist, syntethic resin, ect.) is deposited on a substrate,
forming the inside of the measuring channel, on top of which a wall
forming layer is deposited (by ie. spin on, drop on, evaporation,
etc. techniques) where the layer not only covers at least part of
the dissolvable substance but also at least a part of the
substrate. The wall forming layer adheres well on the substrate and
forms the measuring channel together with the substrate. The
dissolvable substance can be dissolved and removed through the
inlet and/or outlet orifices of the measuring channel.
The invention discloses furthermore a tube connection,
characterized in that at least one tube, which can be connected
with the substrate ie. by gravity forces, glue, ect. is covered by
a layer, formed by drop on, evaporaton, sputtering, spin on, ect.
procedures and which forms a tight seal with the tube and the
substrate. The tube ending is kept open by the layer that, together
with the substrate, forms a cavity which represents a continuation
of the tube.
The invention also discloses the fabrication procedure of the tube
connector, characterized in that on a substrate and at least one
tube, which can be connected to the substrate, ie. by a glue, a
dissolvable substance, ie. photoresist, synthetic resin, ect. is
deposited forming a continuation of the tube. A layer is deposited
on top of at least part of the dissolvable substance and on at
least part of the tube and at least part of the substrate by ie.
drop on, sputtering, spin on, etc. techniques which is tightly
adhering on the tube and substrate; afterwards, the dissolvable
substance is dissolved and removed through the tube or the orifice
of the tube continuation, which is formed by the layer and the
substrate.
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